fast-twitch
adjective
: of, relating to, or being muscle fiber that contracts quickly especially during brief high-intensity physical activity requiring strength compare slow-twitch
Examples of fast-twitch in a Sentence
Recent Examples on the Web
This muscle type is also more efficient than fast-twitch, which are generally higher in men’s muscles.
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The Washington Post, San Diego Union-Tribune, 17 June 2025
At a certain point, Crow-Armstrong’s instincts and fast-twitch reflexes take over.
—Patrick Mooney, New York Times, 15 June 2025
On the other hand, type 2 muscle fibers (a.k.a, fast-twitch) power anaerobic work, or that which taps into strength and power—yes, like lifting—which can’t be sustained for a long time, Dr. Aguillard explains.
—Danielle Zickl, SELF, 11 June 2025
Some people may have a higher proportion of fast-twitch muscle fibers with greater growth potential.
—Alyssa Hui-Anderson, Verywell Health, 16 May 2025
For examples, men tend to have more muscle mass, a larger store of fast-twitch muscle fibers, and a higher VO2 max, or the maximum rate of oxygen intake.
—Mia Cathell, The Washington Examiner, 27 Apr. 2025
During intense exercise, the pH in your fast-twitch muscle fibers (which seem to be particularly susceptible to hydrogen ion buildup) can drop from around 7.0 to 6.0.
—Alex Hutchinson, Outside Online, 24 Apr. 2025
It is largely driven by the loss of fast-twitch muscle fibers—responsible for explosive movements—and declines in reactivity, or the ability to respond quickly to a threat, such as a misstep on uneven ground.
—Jesse Pines, Forbes.com, 8 Apr. 2025
In addition, explosive exercises like sprinting and skipping help retain fast-twitch muscle fibers, crucial for power and reaction time.
—Jesse Pines, Forbes, 24 Mar. 2025
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The Washington Post, San Diego Union-Tribune, 17 June 2025
At a certain point, Crow-Armstrong’s instincts and fast-twitch reflexes take over.
—Patrick Mooney, New York Times, 15 June 2025
On the other hand, type 2 muscle fibers (a.k.a, fast-twitch) power anaerobic work, or that which taps into strength and power—yes, like lifting—which can’t be sustained for a long time, Dr. Aguillard explains.
—Danielle Zickl, SELF, 11 June 2025
Some people may have a higher proportion of fast-twitch muscle fibers with greater growth potential.
—Alyssa Hui-Anderson, Verywell Health, 16 May 2025
For examples, men tend to have more muscle mass, a larger store of fast-twitch muscle fibers, and a higher VO2 max, or the maximum rate of oxygen intake.
—Mia Cathell, The Washington Examiner, 27 Apr. 2025
During intense exercise, the pH in your fast-twitch muscle fibers (which seem to be particularly susceptible to hydrogen ion buildup) can drop from around 7.0 to 6.0.
—Alex Hutchinson, Outside Online, 24 Apr. 2025
It is largely driven by the loss of fast-twitch muscle fibers—responsible for explosive movements—and declines in reactivity, or the ability to respond quickly to a threat, such as a misstep on uneven ground.
—Jesse Pines, Forbes.com, 8 Apr. 2025
In addition, explosive exercises like sprinting and skipping help retain fast-twitch muscle fibers, crucial for power and reaction time.
—Jesse Pines, Forbes, 24 Mar. 2025
Cite this Entry
“Fast-twitch.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fast-twitch. Accessed 1 Jul. 2025.
Copy CitationMedical Definition
fast-twitch
adjective
: of, relating to, or being muscle fiber that contracts quickly especially during brief high-intensity physical activity requiring strength compare slow-twitch
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